#include<iostream>
using namespace std;

int adj[1001][1001];

int main()
{
	int n, m, a[1001], u[24001], v[24001];

	cin >> n >> m;

	for (int i = 1; i <= n; i++)
	{
		cin >> a[i];
	}

	for (int i = 1; i <= m; i++)
	{
		cin >> u[i] >> v[i];
		adj[u[i]][v[i]] = 1;
		adj[v[i]][u[i]] = 1;
	}

	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= n; j++)
		{
			if (adj[i][j] == 1)
			{
				for (int k = 1; k <= n; k++)
				{
					if (adj[j][k] == 1)
					{
						if ((((a[i] < a[j]) && (a[k] < a[j])) || ((a[i] > a[j]) && (a[k] > a[j]))) && a[i] != a[k])
						{
							cout << "YES" << endl;
							return 0;
						}
					}
				}
			}
		}
	}
	cout << "NO" << endl;
}